1. Field of the Invention
The present invention relates to a drawing instrument, and more particularly to a pen track that can draw undulating lines regularly without using auxiliary tools.
2. Description of Related Art
When users paint posters by hands or making cards, users may draw undulating lines. In a conventional drawing method, the users need to prepare an auxiliary tool such as a ruler, a french curve or a curve plate to enable a pen to abut a contour of the auxiliary tool to draw lines. However, the users need to prepare the auxiliary tool in advance, and the auxiliary tool may be slid when the users apply an excessive force to abut the auxiliary tool. Then, the lines cannot be drawn according to the contour of the auxiliary tool. Furthermore, the auxiliary tool has a limited length, and the users need to constantly move the auxiliary tool to extend the length of line. This is inconvenient in use and a gap may be generated at the convergence of lines. Additionally, the auxiliary tool usually has a specific contour, and the users need to prepare multiple auxiliary tools of different contours when the users want to draw undulating lines of different types. In view of the above-mentioned problems, the conventional drawing method is inconvenient in use and is prone to drawing errors when the users want to draw undulating lines.
To overcome the shortcomings, the present invention tends to provide a pen track to mitigate the aforementioned problems.